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A method for the synthesis of propargylic formates from propargylic alcohols and sodium chlorodifluoroacetate is reported. In the reaction, sodium chlorodifluoroacetate is used as a difluorocarbene precursor and a formylating reagent to provide a carbonyl source, while the triple bond of propargylic alcohols is not involved. The method shows convenient operation, good functional group tolerance and high site‐selectivity under mild reaction conditions. [ABSTRACT FROM AUTHOR]

Abstract Selenophenolato hydrido iron(II) complexes 1–3 cis- [(H)(SeAr)Fe(PMe 3) 4 ] (Ar = C 6 H 5 (1), p -MeOC 6 H 4 (2) and o -MeC 6 H 4 (3)) could catalyze transfer hydrogenation of aldehydes and ketones. Among the three complexes, catalyst 1 exhibited the highest catalytic activity. The catalytic reactions took place under very mild conditions, using isopropanol as solvent and hydrogen source, tBuONa as base under 60–80 °C. This catalytic system has good tolerance for many functional groups, such as halides, C C double bonds, nitro groups and cyano groups at the phenyl ring of the substrates. Graphical abstract Unlabelled Image Highlights • Selenophenolato iron(II) hydride could catalyze transfer hydrogenation of aldehydes and ketones. • The catalytic system has tolerance to many functional groups. • This catalytic system is suitable for selective transfer hydrogenation of cinnamaldehydes. [ABSTRACT FROM AUTHOR]

An efficient synthesis of α‐oxoalkyl ketones is described. The current method is the coupling reaction of phenyl vinyl azides and cyclic ethers under metal‐free conditions. The reaction is conducted with KI as the additive and TBHP (70 % solution in water) as the oxidant at 60 °C for 12 h. A wide range of α‐oxyalkylated ketones with broad functionalities has been synthesized in moderate to good yields. [ABSTRACT FROM AUTHOR]

Abstract: An ultrafast and highly efficient ligand-free Suzuki–Miyaura cross-coupling reaction between aryl bromides/iodides and arylboronic acids using palladium chloride as catalyst in PEG400/H2O in air at room temperature has been developed. TEM showed that palladium nanoparticles were generated in situ from PdCl2/PEG400/H2O without use of other reductants. The catalyst system can be recycled to reuse three times with good yields. [Copyright &y& Elsevier]

[image omitted] The indium-mediated Barbier-type allylation reaction of aldehydes with allyl bromide, which gives corresponding homoallyl alcohols, was investigated. The reaction medium and the effects of substituents were discussed in detail. The results showed that various aldehydes, including aromatic, heterocyclic, and aliphatic aldehydes, with different substituents could all react well with excellent yields of 91-97% in aqueous tetrahydrofuran at room temperature within about 1 h. [ABSTRACT FROM AUTHOR]

A rapid and efficient Heck coupling reaction of aryl iodides with terminal olefins was conducted in PEG-400 at 120 ˚C in the presence of potassium carbonate and palladium nanoparticles formed in situ from palladium chloride under focused microwave irradiation. High to excellent product yields were achieved. The reaction medium and catalyst could be easily recycled at least five times without significant loss in reactivity. [ABSTRACT FROM AUTHOR]

Abstract: Environmentally friendly and effective removal of Br− and Cl− impurities in hydrophilic dialkylimdazolium or butylpyridinium ionic liquids was investigated and developed at room temperature to 80°C and atomspheric pressure. Constant elelctrolysis was applied to oxidize Br− and Cl− to their corresponding Br2 and Cl2, then the and ions from HBF4 and HNO3 solution in the cathode zone move to anode zone through an anion exchange membrane and combine with dialkylimdazolium or butylpyridinium cation to form ionic liquids. The Br2 and Cl2 in electrolyzed ionic liquids are treated with ethylene to afford the corresponding 1,2-dibromo (or dichloro) ethane which could easily be removed by volatilisation under vacuum (ca. 10mmHg). Removal of Br− and Cl−impurities (0.94–4.47wt%) from hydrophilic dialkyl imdazolium or butylpyridinium ionic liquids through electrolysis and ethylene treatment could be achieved at 0.06%–0.29% without any additional solvents and ionic liquid loss. [Copyright &y& Elsevier]

Abstract: Several novel sulfonyl chloride functionalized ionic materials were used as media and catalysts for Beckmann rearrangement of cyclohexanone oxime and satisfactory results were achieved under mild conditions. The effects of all parameters were discussed. Moreover, the deactivation of ionic liquid catalytic system during the recycle was investigated by using FTIR spectroscopy and mass balance calculation. The trapping of acidic ionic material with basic product is proved to be mainly responsible for the difficulties encountered in the reuse of this type of material. A possible mechanism was conjectured. [Copyright &y& Elsevier]

Novel sulfonyl-functionalized ionic liquids (SFIL) with –SO 3 H and &sbnd;SO 2 Cl groups have been designed, synthesized, and characterized. Being strong acidic substances, these ionic liquids have great potential as media and catalysts in many acid-catalyzed reactions. [ABSTRACT FROM AUTHOR]

β-Amino secondary alcohols were formed by aminolysis of epichlorohydrin and styrene oxide with aromatic amines using aqueous ethanol (1:1) as the solvent in conjunction with microwave irradiation without a catalyst. The methodology is fast, efficient, highly regioselective, chemoselective and environmentally benign. [ABSTRACT FROM AUTHOR]

A green method for the allylation of aldehydes with allyl bromide mediated by indium in polyethylene glycol 400 (PEG400) and PEG400/H2O is described. Aldehydes with different substituents afforded the corresponding homoallylic alcohols in good to excellent yields. Comparative studies show that water promoted this reaction in PEG 400. [ABSTRACT FROM AUTHOR]

Abstract: Indium-mediated one-pot esterification reaction of acyl chlorides or anhydride by using in situ-prepared homoallyl alcohols from aromatic aldehydes and allyl bromide proceeded smoothly to afford the corresponding homoallyl alcohol esters in high yields within about 1h, which provided a simple and efficient protocol for the simultaneous allylation and esterification of aldehydes without other catalysts and dehydrants. [Copyright &y& Elsevier]

A Pd‐catalyzed three‐component intermolecular reaction between aryl halides, ClCF2COONa and phenols is developed. A series of aryl benzoates were synthesized in up to 84 % yield via difluorocarbene transfer carbonylation. It is devoted to acquiring the targeted products by construction of new C−C, C=O and C−O bonds in a one‐pot, one‐step process. The feature of this method includes the use of readily available starting materials, showing outstanding resistance to spatial obstruction and simple operation procedure with mild reaction conditions. Therefore, this makes the methodology a useful alternative to other schemes typically used for the synthesis of aryl esters. [ABSTRACT FROM AUTHOR]

An efficient, general, inexpensive, and environmentally friendly photosynthesis of sulfonamides via visible light promoted debenzylative sulfonylation of tertiary benzylamines is described. Compared to the traditional S−N coupling reactions, which are promoted by oxidative C−N bond cleavage of symmetrical tertiary alkylamines, this strategy provides a selective C−N bond cleavage protocol and avoids the use of transition‐metal, explosive oxidants, and ligands. [ABSTRACT FROM AUTHOR]

A novel one-pot, three-component reaction of 2-aminothiophenols, aldehydes and malononitrile was studied under electrochemical conditions. The reaction was conducted using TBABF4 as an electrolyte and CuI as a catalyst in an undivided cell at room temperature. The proposed reaction mechanism showed that CuI acted as an "electron relay". [ABSTRACT FROM AUTHOR]

A novel Pd-catalyzed assembly of N-substituted phthalimides by merging of [4+1] cycloaddition and difluorocarbene transfer carbonylation from 2-iodo-N-phenylbenzamides and difluorocarbene precursors is disclosed. Difluorocarbene acts as a carbonyl source and simultaneously forms one C–C bond, one C–N bond and one C＝O bond to produce N-substituted phthalimides in high yields. [ABSTRACT FROM AUTHOR]

A Cu/Pd co‐catalyzed Catellani‐type ortho arylation reaction of iodoarenes with aryl diazonium salts has been developed. Aryl radicals that derived from aryl diazonium salts were regioselectively installed at ortho position of iodoarenes via palladium catalyzed C−H activation. Mechanistic studies showed that, in contrast to classical Pd0−PdII−PdIV−PdII−Pd0 catalytic cycle, this radical cascades performed via a Pd0−PdII−PdIII−PdI−Pd0 cycle. [ABSTRACT FROM AUTHOR]

This amination method has a wide substrate scope and broad functional group tolerance. [ABSTRACT FROM AUTHOR]

Organozinc pivalates, a recently developed air‐ and moisture‐stable organozinc species, were found for the first time as excellent organometallic species in the monoorganylation of trialkyl borates whereby boronic acids were prepared in high yields. The significant advantage of organozinc pivalates over another previously employed organometallic reagents, e. g. organolithium reagents, Grignard reagents and organozinc halides, is that the generation of multiorganylation byproducts such as borinic acids and trialkylboranes were completely suppressed. Additionally, the in situ generated boronates could be directly arranged into Suzuki‐Miyaura type cross‐coupling reactions to produce biaryls in high yields. Far from boring! Organozinc pivalates were proven as an excellent organometallic species in the mono‐organylation of trialkyl borates whereby boronic acids and their esters were prepared in high yields. [ABSTRACT FROM AUTHOR]

Cu(BTC)-MOF catalyzed one-pot, three-component reaction of terminal alkynes, halides and sodium azide to form 1,4-disubstituted-1,2,3-triazoles was investigated. It was conducted in methanol under room temperature with good to excellent product yields. The Cu(BTC)-MOF catalyst could be easily recovered by filtration and be reused at least three recycles with no significant decrease in the yield. The method was demonstrated to be a truly green process with sustainability and economics. [ABSTRACT FROM AUTHOR]

The reaction tolerates aliphatic halides and benzylic halides, with bromides providing higher yields than chlorides. [ABSTRACT FROM AUTHOR]

A simple and efficient method for α-alkylation of ketones with primary alcohols catalyzed by RhCl(CO)(PPh 3 ) 2 without additional additives under mild conditions is developed. It has a wide substrate scope, high atom-efficiency and chemoselectivity. It is an environmentally friendly method to build C C bond because water is the only byproduct. [ABSTRACT FROM AUTHOR]

A mild electrochemical method was developed for the direct C2 sulfonylation of heteroaromatic N‐oxides with sulfonyl hydrazides to obtain a serial of 2‐sulfonyl quinoline/pyridine derivatives. The method has simple conditions, using potassium carbonate as base, CH3CN/H2O (9 : 1) as solvent, and reacting for 3 h under 15 mA current to prepare expected products. [ABSTRACT FROM AUTHOR]

The palladium/norbornene co‐catalyzed difunctionalization of haloarenes provides a facile and efficient method for the synthesis of polyfunctional aromatic compounds. However, the suitable substrates for such a transformation have been strictly limited to haloarenes. We here demonstrate that aryl diazonium salts could be well employed as substrates in these reactions, enabling arylbromides with electron‐withdrawing groups to be used as cross‐coupling partners. [ABSTRACT FROM AUTHOR]

Interfacial layers between active layer and electrodes are essential for achieving high performance in organic solar cells. Herein, an effective anode interface modification material, TTF-PZ was synthesized and combined with PEDOT:PSS using as hole transporting bilayer. The bilayer-containing routine solar cell consists of PM6: Y6 bulk heterojunction delivered an increased PCE of 15.84% and an impressive J sc of 26.19 mA/cm2. The underlying mechanisms of such improvement can be summarized as below: the optimization of the active layer morphology, effective charge extraction, and decreased charge recombination. This work confirms the possibility that TTF-PZ could be used as a hole transport material to obtain high performance in organic photovoltaic field. • A non-planar conjugated TTF-PZ used as buffer layers in PM:Y6 organic solar cells for the first time. • The device based on TTF-PZ/PEDOT:PSS bilayered HTLs yielded a 15.84% PCE with an J sc of 26.19 mA/cm2. • The reason for the higher J sc with bilayer structure was confirmed. [ABSTRACT FROM AUTHOR]

A simple oxidative cross-coupling reaction between vinyl azides and sodium sulfinates was developed. This reaction uses commercial arylsulfinates that are more efficient, cheaper, and more stable as sulfonylation reagents, for efficiently, cheaply, and environmentally friendly synthesis of β-keto sulfones. And the reaction has the advantages of simple operation, high efficiency, good yield, and also has a wide range of functional group tolerance. [ABSTRACT FROM AUTHOR]

A visible-light photoinduced ring opening of N-alkyl-4-piperidinols under mild conditions has been achieved. The reaction sequence involves a visible-light-induced charge-transfer complex, which promoted the S–Cl bond cleavage of sulfonyl chlorides. The generated sulfonyl radical further reacts with N-alkyl-4-piperidinol cation radicals to achieve C–N and C–C bond cleavages to yield homoallylamine products. [ABSTRACT FROM AUTHOR]

An efficient, inexpensive and environmentally friendly synthesis of β‐ketosulfones, via NaI‐catalyzed oxidative sulfonylation of ketones with zinc sulfinates, employing ethylene dibromide (EDB) and air as the oxidants, is described. EDB was shown to be a mild organic oxidant to convert NaI into molecular iodine that promote the cross‐coupling reactions of zinc sulfinates with ketones, producing β‐ketosulfones. Mechanistic studies indicated that a radical pathway might be involved in the reaction process. The key feature of the present protocol is the far greater solubility of NaI and sulfinates in micellar arrays present in aqueous solution where the oxidative coupling reactions are taking place. [ABSTRACT FROM AUTHOR]

Organic molecules containing α-triazolyl or β-amino cyclic ketone fragments have been individually proven to show good bioactivities and to be useful in asymmetric and pharmaceutical syntheses. A triflic acid-promoted simple and efficient method for the synthesis of unsymmetrical α-triazolyl-α′-(aminomethyl)cycloalkanones from benzyl azides and α-triazolylcycloalkanones has been developed. A series of unsymmetrical α,α′-disubstituted cycloalkanones were obtained with high syn -diastereoselectivity and up to 82% yield. Examination of the reaction mechanism showed that the benzyl azides undergo protonation, nitrogen elimination, rearrangement, and electrophilic attack by the enol forms of the cyclic ketones. [ABSTRACT FROM AUTHOR]

An efficient copper-catalyzed arylation reaction of 1-acyl-1 H -1,2,3-benzotriazoles with diaryliodonium salts via C–N activation is explored. The reaction is conducted regioselectively to form 1-aryl-1 H -1,2,3-benzotriazoles in MeCN at 80 °C in the presence of cesium carbonate. 29 examples are given with the product yield of up to 84%. The probable reaction mechanism is proposed. Image 1 • It involves an original C–N bond cleavage and a new C–N bond formation in one-step reaction. • Commercial available copper powder is a high efficient and cheap catalyst for this reaction without addition of any ligands. • The reaction has wide scope of substrates (1-acyl-1 H -1,2,3-benzotriazoles and diaryliodonium salts) and good group tolerance. • The products of this method contain 1,2,3-benzotriazole building block. They may have some bioactivities and can be used as pharmaceutical candidates. [ABSTRACT FROM AUTHOR]

A novel charge‐transfer complex triggered sulfonylation of 1,4‐diazabicyclo[2.2.2]octane (DABCO) with mild reaction conditions has been developed. The formation of a charge‐transfer complex between electron‐withdrawing (hetero)aryl sulfonyl chloride and DABCO allows the synthesis of N‐ethylated piperazine sulfonamide in good yields. The reaction has a high functional group tolerance. Spectroscopic studies confirmed the charge‐transfer complex formation between sulfonyl chlorides and DABCO, which facilitates the C−N bond cleavage of DABCO. Trigger happy: A novel charge transfer complex triggered sulfonylation of 1,4‐diazabicyclo[2.2.2]octane (DABCO) with mild reaction conditions is been developed. [ABSTRACT FROM AUTHOR]

A novel NaI‐catalyzed oxidative amination of sodium sulfinates, employing both ethylene dibromide (EDB) and air as the oxidants, is described. EDB was first demonstrated to be a promising mild organic oxidant that in air, converted NaI into molecular iodine to promote the cross‐coupling reactions of aromatic sodium sulfinates with amines to produce arylsulfonamides. Mechanistic studies indicated that a radical pathway might be involved in the reaction process. A novel NaI‐catalyzed oxidative amination of sodium sulfinates, employing both ethylene dibromide (EDB) and air as the oxidants, is described. [ABSTRACT FROM AUTHOR]

Abstract: A catalyst‐free, charge‐transfer complex promoted coupling of sulfonyl chlorides with vicinal tertiary diamines to generate sulfonamides is presented. Mechanistic studies showed that these reactions are proceeded via charge transfer of vicinal tertiary diamines to sulfonyl chlorides, forming the unstable sulfonyl quaternary ammonium like complexes which induced the regiospecific intramolecular C−N bond cleavage of vicinal tertiary diamines. [ABSTRACT FROM AUTHOR]

A novel organozincate of RMgX ⋅MeZnOMe ⋅LiCl type, formed in situ via transmetalation of Grignard reagent RMgBr ⋅LiCl with MeZnOMe, is shown to be an excellent organometallic species in the nucleophilic addition/Oppenauer oxidation of aldehydes to generate aromatic ketones in high yield. This transformation allows quick access to structurally diverse aryl, heteroaryl, benzyl and alkyl ketones with broad substrate scope and excellent functional group tolerance. [ABSTRACT FROM AUTHOR]

A Cu(0)‐catalyzed multicomponent reaction of tetrahydroisoquinolines (THIQ), paraformaldehyde and terminal alkynes to form propargylamines is developed. This protocol worked well for other secondary amines too. Acetylene‐Mannich products were obtained in high yields (up to 98% yields). This acetylene‐Mannich reaction is operationally simple, scalable and exhibits high functional‐group tolerance. A copper powder‐catalyzed acetylene‐Mannich reaction involving tetrahydroisoquinolines (THIQ) and paraformaldehyde to form N‐propargylation products in one‐pot sequence is developed. This protocol is suitable for other secondary amines as well as various substituted phenylacetylenes. THIQ C1‐alknylation is not found. [ABSTRACT FROM AUTHOR]

The Stille coupling of organotin compounds with aryl iodides and aryl bromides catalysed by in situ formed nanoparticles from commercially available palladium dichloride in PEG-400 in the presence of DMAP under microwave irradiation has been developed. For tetraphenylstannane, the reaction was carried out in an atom-efficient way, as 4 equiv. of aryl halides coupled effectively with 1 equiv. of tetraphenylstannane to furnish 4 equiv. of the corresponding functionalised biaryls in high yields. Under the same conditions, PhSnBu3 also reacted with aryl halides to produce biphenyls. [ABSTRACT FROM AUTHOR]

Abstract: Three-component reaction of alkyl halides, sodium azide with terminal alkynes can be catalyzed by nano-copper particles under ambient conditions. A series of 1,4-disubstituted-1,2,3-triazoles were obtained regioselectively by this one-pot strategy. Nano copper can be reused at least three times without significant deactivation. [Copyright &y& Elsevier]

Abstract: Sixteen 5-unsubstituted-3,4-dihydropyrimidin-2(1H)-ones have been synthesized by microwave-assisted Biginelli reactions in a short and concise manner employing ZnI2 as a catalyst under solvent-free conditions. All products were identified by IR, NMR, elemental analysis and HRMS. The advantages of this novel protocol include the excellent yield, operational simplicity, short time and the avoidance of the use of organic solvents and expensive catalysts. [Copyright &y& Elsevier]

An abstract of the article "The Influence of Main Group Metallic Lewis Acids on the Formation and Reactivity of Grignard Reagents" by Ying Fu and colleagues is presented.

An efficient and ligand-free method for the Stille coupling is reported leading to biaryls (III) in moderate to excellent yields. [ABSTRACT FROM AUTHOR]

Copper nanoparticles catalyze the reaction of alkynes, alkyl halides, and sodium azide to give the title compounds with high regioselectivity. [ABSTRACT FROM AUTHOR]

A diagram is presented which shows the oxidation of aromatic aldehydes to aryl ketones using triorganoaluminum reagents.

Depending on the conditions A) or B) mono- and diolefinated dihydrophthalazines such as (III) and (IV) are generated. [ABSTRACT FROM AUTHOR]